Radio loud-speaking receiver



Nov. 1o, 1925:,Y l 1,569,779

P. S. GRIERSON RADIO LOUD SPEAKING RECEIVER Filed Sept. 6, 1922 Br K rable `in a simple manner by the user or op-` Patented Nov. 1o, 1925.

UNITED STATES PATENT- OFFICE;-

PAUL S. GRIERSON, SOUTH ORANGE, NEW JERSEY, AASSIGNOR TO CHARLES CORY &SON, INC., OF NEW YORK, N. Y., A CORPORATION 0F NEW YORK.

RADIO IiOUD-SPEAKING RECEIVER.

Application led September 6,' 1922.V lSerial No.l"586,456.

fo all whom it may concern: v

lBe it known that I, yPAUL S. GRIEnsoN, a citizen ofthe United States,andresident of South Orange, inthe county of Essex and State of NewJersey, have invented certain new and useful Improvements in RadioLoud-Speaking Receivers, of which the followingis a specification.

This invention relates to a telephone receiver, and more particularly toa loud speaking telephone receiver especially adapted for employmentwith radio receiving apparatus. i

A prime desideraturn of my present in-k vention comprehends theprovision of a telephone receiver; especially intended for radioreceiving sets constructed anddesigned to produce clear and loud tonesfor the faithful and efficient reproduction of speech, the receiverbeing constructed so as to be ,adjusterator in accordance with thevarying needs of service. j l y Invthe reception 'of radio telephonieimpulses and the conversion the same to audio impulses, the eiiciency ofthetelephone receiver used is dependent upon a number of importantfactors. One of the more important considerations resides in the factthat a telephoney receiver, where a maximum sound emitting eiliciency isdesired, must be adapted tol a given receiving set and. to the locationof such set relatively to the radio sending station, by reason of thefact that ,different degrees of pulses for energizing the magnet coilsof the telephone receiver bein therefore of strength varying with theparticular set and receiving station. To produce mamum sound 'effectsunder any and all of these varying conditions, the receiver should beadapte tosuch vvarying degrees of strength of impulses, and theprovision of such a receiver which may be adjusted to fit the varying orweakness needs of service is a principal object of the presentinvention.

-The principal objects of my present invention may be' said to includethe provision of a radio telephone receiver which is adaptable to agiven receiving set under differing conditions of service for adjustingfor a maximum sound efficiency with a` a sensitive adjustment may bemade by the user -or operator in a simple manner; the further provisionof a radio telephone receiver in which discordant vibrations of theelectromagnet unit is minimized so as to permit of obtaining pure andclear tones; the still further provision of a telephone receiver of thenature referred to in which theparts are constructed and relativelyarthe efficient operation of the receiver is de-fwranged to provide astable unit having a low center of gravity and the further provision ofa telephone receiver made of a few parts which are easily assembled anddisassembled for purposes of inspection and repair, with the partsinter-relatedto pro-v videa loud-speaking receiver of attractiveappearance.V Y

To the accomplishment of the foregoing and. such other objects as may`hereinafter appear, my invention consists in the ele-.

ments and their relation one to the other, as hereinafter .particularlydescribed and o5 S' sought to be denedin the claims, reference being had`to the accompanying drawing which shows a preferred embodiment of myinvention, and in which v Fig. 1 is a side elevational view of myimproved radio telephone receiver, Fig. 2 is a cross-sectional view withthe horn cut away,

Fig. 3 is a View taken in cross-section on the line 3 3, Fig. 2, l Fig.at is a view taken in cross-section on the line 4 4, Fig. 3, and

Fig. 5 is a bottom plan view of parts of the receiver shown in a reducedscale.

Referring now more. in detail to the drawthereof ings, the receivercoii'iprises a supporting base B which may be made forexample of Wood, acasing C carried by and attached tothe base B by any approved means suchas the spaced screws l() which secure a marginal flange portion 11 ofthe casing C to the base B, vthe said casing comprising a body portion12 housing the diaphragn'i D and the electromagnetic unit E and a cover13 removably attachable to the casing body 1-2, the said cover beingprovided with a vision of an improved radio telephonie re-` central boss14 for receiving the amplifying horn 15.

As heretofore referred to, a principal object of the inventioncomprehends the .pro-

ceiver which is adjustable for producing a maximum .sound ei'liciency-with a given strength of received impulse. To accomplish this end, myinvention comprises the provision of a telephone receiver in which thediaphragm D and the electromagnet unit E are movable relatively to eachothery to vary the distance between the same, the

one being adjustably settable relatively to the other. For a givenstrength of current energizing the coils of the electromavnet E, thediaphragm D has a critical position for maximum'eiiiciency, and must belocated a given distance from the coils for a given 5.strength ofenergizing current, the diaphragm having different .critical positionsor different strengths of energizing cur-4 rents. By the relativeadjustment, therefore, of the diaphragm and the electromagnet, coils,vand by the provision of means whereby the diaphragm and the electromaet may be set or held in any adjusted position one' relatively totheother, the

characteristics of the receiver may be varied the casing C in a manneraswill be detailed hereinafter, and by mounting 'the diaphragm D so as tobe adjustably settable withrespect to the electromagnet E, the

said diaphragm D being to this end carried.

by and attached to the cover 13 as by means of clamping the same betweenthev said cover and a clamping ring 16, the said clamping ring 16 beingattached to the cover by means of the securing screws 17, the clampingring being adjustably movable in the casing body 12, the clamping ringbeing to this'end externally threaded as at 18 for engagement with thecomplemental threaded portion 19 of the casing body l2. lith thisconstruction the casing cover 13 and the diaphragm D carried thereby maybe microscopically adjusted and the distance between the diaphragm D andelectromagnet E varied in slight degrees for producing a sensitiveadjustment. e

For the purpose of holding or setting the diaphragm D in any adjustedposition, I provide locking means inthe form of a set screw 20 threadedthrough altapped bore in the casingbody 12 and engageable with adepending skirt or flange portion 21 forming part of the clamping ring16. By the the receiver may be quickly adapted to a provislon ofthismeans it will be seen that I given strength of received impulse by lprovided with the opposite poles 23 and 2-1- to which is attached thelaminated L-shaped core pieces 25 and 26, the legs of the core' piecesforming the cores for the-electromagnet coils 27 and 28 respectively,the feet of the core pieces being magnetically secured to the polepieces 23 and 24, a non-magnetic clamping ring 29 in conjunction withthe non-magnetic clamp pieces 30 and 31 being provided for clamping thecore pieces to the magnet member 22, the screws 32 being provided forsecuring these parts together. The

-weighting magnet member 22 is designedly massive, and ispositioned inacentral openors4 ing 33 of the base B and is attached "to i the bottom34 of the casing C as by means of securing screws 35 so as to besubstantially housed by the said base,'the mass` and the position ofthis Weighting magnet member producing a telephone receiving unit havingthe desired stability and low center of gravity.

For the purpose of providing a radio telephone receiver in whichdiscordant vibrations of the electromagnet unit E` are minimized so asto'permit of the obtaining pf pure and clear tones, If provide meansoutput end of la receiving set, there is .for absorbingithe vibrationsof the. electro- For the purpose of preventing any abnormal stress onthe diaphragm during adjustl'ment of the same to obviate thepossibility' of injuring -the same, I provide a construction in whichmotion of the diaphragm D towards the electromagnet E is limited in 'apredetermined manner, the cover 13 and the casing body 12 beingconstructed to provide the stop or l'limiting means; and to this end thetop marginal edge of the body 12 is made substantiallyflush withl thepole faces of the cores 25 and 26 and is adapted to engage theunderneath wall of the cover 13 in the limiting f positiom to the samebeing prevented. v For connecting the electromagnet coils 27 Aand 28 to'the rovided t el spaced binbdingpostsf38 an 39 nected to the coils bymeans tors 40 and 4l. respectively. y

The method of making and using my imof the lconducproved radiotelephonejreceiver will.y inl theu r main be. apparent from' the abovedetailed description thereof. It will be apparent that by the provisionof the adjustably'settable diaphragm D that quick andsensitive-vadjustment may be made a simple manner by the operator oruser for compensatinv for different strengths ,of incoming ysigna s.or

impulses and for adapting the telephone receiver to the characteristicsof any particular radio receiving set. It will be further apparent thatwith my improved construction a very stable, strong and durable unit isprovided, with the parts inter-related to form a presentable andattractive receiving device. v v

While Ifhave shown my device in the preferred form, it will be apparentthat many changes and modifications may be made in the structuredisclosed, without departing from the spirit of the invention, definedin the following claims.

I claim;

1-. A telephone receiver comprising a casing, an electromagnetic meanshoused thereby, a cover for the casing, a1 di'aphragm'associated withsaid electromagnetic means, a ring clamping the diaphragm to the coverand. having threaded engagement. within theto'vary the distance-betweenthe diaph and the said means, the said ring 'and' asing. beingconstructed to limit the By this means thel diaphragm cannot bedisplaced or distorted. to yield any abnormal stresstherein, damagemovement olf the diaphragm towards theV vide a low vcenter of gravityfor the receiver, an electromagnet carriedby said member,

the electromagnet, and a diaphragm associated with said electromagnet.3. In a telephone receiver, an outer casing,

4thesaid member providing magnet poles for electromagnet coil means, adiaphragm vi-' bratable thereby, and provisions for dampening vibrationsof -said coil means comprising a non-magnetic inner lcasing Vcontaining\said means and filled with a vibra- .tion absorbing substance.

4. In a telephone receiver, an electromagnet unit comprising an outercasing, spaced coils, L-shaped core pieces one'for each coil,

and a magnet member, the leg of .each core piece forming the core of themagnet coil with the foot of each corepieceattached to the said magnetmember, andprovisions for dampening vibrations of the said electromagnetunt comprising an enclosure containing Said .coils and fiueawah a vibra:tion absorbing substance. carried bythe base Band electrically con- 5.`A telephone receiver or loud speale proximately annular stabilizingmagnet dey i pendently secured to lthe casing and accomfmodatedin anaperture in the base, said magnet having substantially opposite inwardlyprojecting'pole members, and elec-4 tro-magnet within the casing andyhaving core members magnetically secured to said pole members anwindings on upwardly projecting portions of the cores, a dia- .phragmsupported adjacent the pole ends, a or the casing, and a horn mounted inthe cap at an aperture therein.

6. A telephone receiver or loud speaker comprising a base designed forhorizontal support, a casing secured thereto,y anapproximately annularstabilizing magnet dependently secured to the casing and accommodated inan aperture in the base, said magnet having substantially opposite'inwardly projecting pole members, angularly formed magnet core memberseach having a portion magnetically secured to one of said pole membersand an upwardly projecting ortion, magnet coils about the pole memers, anon-magnetic inner casing closely surrounding the magnet windings andvfilled in the 'cap -at an aperture therein.

.a cap`forjth'e casing, and a hornmounted I 7. A telephone receiver-orloud speaker,

comprising a substantially cylindrical casing, an electro-magnettherein, a ring having screw threaded engagement n the casing to providefor adjustment in an axialdirection by rotation of the ring, the ringhaving-an inwardly projecting flange adjacent the casing wall, av setscrew passing'- through a threaded hole in the casing -u'all and adaptedto engage said flange to look the ring in adjusted position, a capsecured to the ring for turning the same to move the diaphragm ring andcap toward and from the eleetro- 10 magnet, the cap having a centralboss and a horn mounted therein. Y l

Signed at New York city, in the county of New York and State of NewYork, this 24th day of August, A. D.-1922.

PAUL S. 'GRIERSON

